College student Emma Strub has been known to take pictures of herself 15 to 20 times a day.

Alone or with friends, smiling or making a goofy face. She shares most of them on photo-messaging app Snapchat, posts others to Instagram, Twitter or tumblr.

She, like so many of her peers, is a master of the smartphone self-portrait — the selfie.

While the selfie is as ancient as MySpace, the snapshots are surging across social media platforms. On Instagram, there are more than 36 million photos tagged #selfie, 98 million tagged #me and countless others without the identifying hashtags. On Snapchat, users exchange more than 200 million photos and videos a day. They’re particularly popular among teens and tweens, and a staple for image-obsessed celebrities like Justin Bieber and Rihanna.

Depending on whom you ask, selfies are either the latest form of self-expression or portraits of narcissism on the rise, society in decline.

Even Strub, 20, acknowledges the absurdity: “Selfies are so stupid, but then I’m sitting here taking 25 at a time.”

Yet the selfie’s popularity suggests something beyond frivolous self-aggrandizing. It hints at a rapidly growing preference for online conversations that prioritize images over words. Clearly, there is a symbiosis between smartphones, social media and selfies.

“Our phones have front-facing cameras for a reason. It’s to take pictures of ourselves,” said Greg Swan, an avid selfie snapper and vice president at public relations firm Weber Shandwick. “People want to share pictures of themselves and what they’re doing.”

Influencing technology

Apple introduced the front-facing camera with the iPhone 4 in 2010, the same year the photo-sharing social network Instagram was born. Then, in 2012 came Snapchat, which exploded in popularity as users traded photos that then vanish.

Video-sharing app Vine was launched in early 2013 without the ability to record through the smartphone’s front-facing camera, only to add that feature in a later update. Hello, video selfie.

When snapping a picture or video is so easy, and there are so many social networks on which to share them, why not?

“They’re funny and they make me smile and I can remember the moment later,” said Strub. “It’s definitely a way of expressing yourself and putting yourself in a light that you can control.”

Yet that focus on image online, especially among young teens, has some worried about a self-absorbed society. After all, research from Harvard University showed that social media users get a bigger neurochemical buzz from sharing information about themselves than sharing information about others.

“There [are] a lot of mixed messages about selfies,” said Pamela Rutledge, a psychologist and director of the Media Psychology Research Center.

She doesn’t see any harm in selfies — people have always liked to see themselves in photographs and sought approval from others — but understands why some people recoil at the sight of so many self-portraits.

“It violates some of those Protestant work ethic kinds of values, how you’re not supposed to brag and you’re not supposed to glorify yourself and all of that,” she said.

A picture says a thousand words

While there are plenty of pictures posted with the goal of getting “likes” for a cute outfit or new hairdo, experts say the onslaught of selfies is changing the way we communicate. Why text “I’m happy” when you could post a picture of your smiling face?

“An image is a much more powerful means of communication,” Rutledge said. “We’re becoming more fluid with text and images supporting one another.”

Snapchat, in particular, pushes communication through images. The photo is front-and-center, and users can choose to add a short caption or doodle on the image before sending it. Fewer words, more pictures.

Because the photos disappear (for the most part) in 10 seconds or less, it’s less about looking good and more about conveying an authentic moment.

“It’s a fun way to talk,” said Kelly McCloskey, 13, of Minnetonka, a regular Snapchat user. “It’s just kind of cooler because you get what they’re saying more.”

Selfie aficionados say the snapshots are a quicker, often more effective way of sharing information.

“Can you imagine me writing, ‘I’m standing in front of the “Spoonbridge and Cherry.” It’s gorgeous. The water’s coming over the cherry and the sun is out,’ ” Swan said. “No. Instead, it’s a selfie shot of me in front of the ‘Spoonbridge and Cherry’ with the skyline in the background.”

That’s the kind of communication Alec Erdahl, 11, had in mind as he prepared for a baseball game on a hot summer afternoon.

In the car, uniform on, he made a face of dread and snapped a selfie.

“Going to baseball with 99 degree weather! #gonnamelt,” he wrote, posting the picture on Instagram.

Erdahl’s stepdad, Sean Lanahan, said he’s heard kids say the photos help them feel connected, especially in the summer when they don’t see their friends as often.

“It keeps that connection visually, which is more impactful than just a simple text,” he said, his stepson nodding in agreement.

Such selfie taking, it seems, is contagious.

When Lanahan’s travel plans changed in the middle of a recent trip, stranding him in Washington, D.C., for an unexpected layover, he slipped into the city.

“I thought the kids might get a kick out of me standing in front of the Capitol and White House,” he said.